Touch sensing device, touch sensing circuit, data driving circuit, and display device driving method

ABSTRACT

The present disclosure provides a touch sensing device, a touch sensing circuit, a data driving circuit, and a display device driving method, which make it possible to activate different sensing areas according to a finger mode and a hover mode, and which activate as many sensing areas as possible simultaneously in a hover mode, which means sensing driving in the case of non-contact with regard to sensing areas, thereby enhancing sensing sensitivity, and improving sensing detection performance even in the hover mode.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from and the benefit under 35 U.S.C.§119(a) of Republic of Korea Patent Application Number 10-2014-0185809filed on Dec. 22, 2014 and Republic of Korea Patent Application Number10-2015-0136677 filed on Sep. 25, 2015, both of which are herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a touch sensing device, a touch sensingcircuit, a data driving circuit, and a display device driving method.

2. Description of the Prior Art

Recently, various user interfaces (UIs) can be implemented by touchsensors provided on display panels having touch functions. Displaypanels including touch sensors are input/output means capable of bothtouch-based input functions and information output functions.

Display panels having capacitive touch functions are advantageous inthat, compared with existing resistive touch panels, they have betterdurability and sharpness and capable of multi-touch recognition andproximity touch recognition, thereby being applicable to variousapplications.

A display panel having a capacitive touch function has a substrate,which includes touch sensors, attached onto the display panel, or thetouch sensors are embedded in the display panel (in-cell type); as aresult, the display panel is electrically coupled with display elements.

Research has recently been conducted such that display panels havingtouch functions can recognize touches not only in a contact touch modesuch as a finger mode, but also in a non-contact touch mode such as ahover mode or a proximity touch mode. As used herein, the contact touchmode refers to a function for enabling recognition of direct touchesmade by a pointer with regard to display panels. The non-contact touchmode means that recognition of a proximity touch or a hovering touch,with regard to display panels, is made possible: in the case of theproximity touch, the pointer does not directly touch the display panel,but is in close proximity therewith and, in the case of the hoveringtouch, the pointer hovers over the touch panel.

Touch functions in the hover mode, among them, with regard to a displaypanel including touch sensors of the in-cell type have not yet beenimplemented.

SUMMARY OF THE INVENTION

It is an aspect of the present invention to provide a touch sensingdevice for maintaining excellent touch recognition sensitivity in adisplay panel, which includes in-cell-type touch sensors, therebyenabling touch recognition in a hover mode.

In one embodiment, a touch integrated display device as well as a drivercircuit or method for driving such a touch integrated display device areprovided. The touch integrated display device, comprises a display panelincluding a plurality of touch electrodes, the display panel operated ina display period of a frame or a touch period of the frame, and a touchdriver circuit to provide a common voltage to the touch electrodesduring the display period and to drive the touch electrodes with a touchdrive signal during the touch period to detect a touch sensing signalresponsive to a touch from the touch electrodes. In a first touch mode,the touch driver circuit drives a first number of the touch electrodeswith the touch drive signal during the touch period. In a second touchmode, the touch driver circuit drives a second number of the touchelectrodes with the touch drive signal during the touch period, thesecond number of the touch electrodes being greater than the firstnumber of the touch electrodes.

For example, the first touch mode may be a contact touch mode in whichthe touch is a physical contact made with the touch integrated displaydevice. The second touch mode may be a non-contact touch mode in whichthe touch does not make physical contact with the touch integrateddisplay device but is within a predetermined distance from the touchintegrated display device. The touch in the non-contact touch mode maybe hovering over the touch integrated display device.

In the first touch mode, the touch drive signal has a referencewaveform. In the second touch mode, the touch drive signal may mimic thereference waveform but an amplitude of the touch drive signal in thesecond touch mode is overdriven by an overdrive amplitude with respectto the reference waveform during an overdrive duration. For example, thereference waveform is a pulse waveform periodically alternating betweena high level and a low level, and the touch drive signal in the secondtouch mode has pulses with two or more different high voltage levelsduring the high level and two or more different low voltage levelsduring the low level.

In another embodiment, a load-free driving signal having the same phaseor amplitude as the touch drive signal is driven to one or more datalines or one or more gate lates of the display panel, while the touchdriver circuit drives the second number of the touch electrodes with thetouch drive signal in the second touch mode.

It is still another aspect of the present invention to provide a touchsensing device, a touch sensing circuit, a data driving circuit, and adisplay device driving method, which can perform touch driving suitablefor each of a contact touch and a non-contact touch.

According to an aspect, the present invention may provide a touchsensing device including: a display panel comprising multiple touchsensors; a sensing signal detection unit configured to supply a drivingsignal for touch recognition to the multiple touch sensors and detect asensing signal through the multiple touch sensors; and a selectioncircuit configured to electrically connect different numbers of touchsensors to the sensing signal detection unit with regard to a case ofcontact touch driving and a case of non-contact touch driving, whereinthe driving signal supplied to the multiple touch sensors in the case ofnon-contact touch driving has a signal intensity larger than the drivingsignal supplied to the multiple touch sensors in the case of contacttouch driving.

According to another aspect, the present invention may provide a touchsensing circuit including: a sensing signal detection unit configured tosuccessively output a driving signal to be applied to multiple touchsensors and detect a sensing signal through the multiple touch sensors;and a selection circuit configured to electrically connect differentnumbers of touch sensors to the sensing signal detection unit withregard to a case of contact touch driving and a case of non-contacttouch driving, wherein the driving signal output in the case ofnon-contact touch driving has a signal intensity larger than the drivingsignal output in the case of contact touch driving.

According to another aspect, the present invention may provide a touchsensing circuit electrically connected to multiple touch sensorsarranged on a display panel, configured to successively supply a drivingsignal to the multiple touch sensors during a touch driving mode,configured to supply a driving signal to one touch sensor at a specifictiming in the case of contact touch driving, and configured to supply adriving signal to two or more touch sensors at a specific timing in thecase of non-contact touch driving, and the driving signal in the case ofnon-contact touch driving has an overdriving period.

According to another aspect, the present invention may provide a touchsensing circuit electrically connected to multiple touch sensorsarranged on a display panel through multiple sensing lines, configuredto successively supply a driving signal to the multiple touch sensorsduring a touch driving mode, and configured to supply a driving signalhaving an overdriving period to two or more touch sensors together at aspecific timing.

According to another aspect, the present invention may provide a touchsensing circuit electrically connected to multiple touch sensorsarranged on a display panel, configured to detect whether a touch occursor not by successively supplying a driving signal to the multiple touchsensors during touch driving, configured to detect whether a touchoccurs or not with regard to each sensing area, which corresponds to onetouch sensor, in the case of contact touch driving, configured to detectwhether a touch occurs or not with regard to each block, whichcorresponds to two or more touch sensors, in the case of non-contacttouch driving, and configured to supply, in the case of non-contacttouch driving, a driving signal having a signal intensity larger than inthe case of contact touch driving.

According to another aspect, the present invention may provide a datadriving circuit electrically connected to multiple data lines arrangedon a display panel, electrically connected to multiple touch sensorsarranged on the display panel, configured to output a data voltage tothe multiple data lines during a display driving mode, configured tosuccessively supply a driving signal to the multiple touch sensorsduring a touch driving mode, configured to supply a driving signal toone touch sensor at a specific timing in the case of contact touchdriving, configured to supply a driving signal to two or more touchsensors at a specific timing in the case of non-contact touch driving,and configured to supply, in the case of non-contact touch driving, adriving signal having a signal intensity larger than in the case ofcontact touch driving.

According to another aspect, the present invention may provide a datadriving circuit electrically connected to multiple data lines arrangedon a display panel, electrically connected to multiple touch sensorsarranged on the display panel through multiple sensing lines, configuredto output a data voltage to the multiple data lines during a displaydriving mode, configured to successively supply a driving signal to themultiple touch sensors during a touch driving mode, and configured tosupply a driving signal having an overdriving period to two or moretouch sensors at a specific timing.

According to another aspect, the present invention may provide a datadriving circuit electrically connected to multiple data lines arrangedon a display panel, electrically connected to multiple touch sensorsarranged on the display panel, configured to output a data voltage tothe multiple data lines during a display driving mode, configured todetect whether a touch occurs or not by successively supplying a drivingsignal to the multiple touch sensors during touch driving, configured todetect whether a touch occurs or not with regard to each sensing area,which corresponds to one touch sensor, in the case of contact touchdriving, configured to detect whether a touch occurs or not with regardto each block, which corresponds to two or more touch sensors, in thecase of non-contact touch driving, and configured to supply, in the caseof non-contact touch driving, a driving signal having a signal intensitylarger than in the case of contact touch driving.

According to another aspect, the present invention may provide a methodfor driving a display device including a display panel on which multipledata lines and multiple gate lines are arranged, a data driving circuitconfigured to drive multiple data lines, and a gate driving circuitconfigured to drive multiple gate lines, the method including:outputting a data voltage to the multiple data lines during a displaydriving mode; and supplying a driving signal successively to themultiple touch sensors embedded in the display panel during a touchdriving mode, wherein, in the supplying a driving signal, a drivingsignal is supplied to one touch sensor at a specific timing in the caseof contact touch driving, a driving signal is supplied to two or moretouch sensors at a specific timing in the case of non-contact touchdriving, and a driving signal having a signal intensity larger than thecase of contact touch driving is supplied in the case of the non-contacttouch driving.

Advantageous effects of a terminal according to the present inventionwill now be described.

In addition, according to at least one of embodiments of the presentinvention, there is an advantage in that, since both a finger mode and asensing mode can be driven, touch detection is possible not only by adirect touch by the user, but also by an indirect touch, i.e.non-contact touch, thereby expanding the range of use of the touchsensing device.

In addition, according to at least one of embodiments of the presentinvention, multiple sensing areas in each sensing area block can beactivated successively in the finger mode. In the finger mode, theuser's direct contact occurs in the sensing areas, and, even if eachsensing area is individually activated, sufficiently large capacitanceof each sensing area makes it possible to detect whether the user'stouch has occurred or not through each sensing area.

In the hover mode, on the other hand, it is possible to detect whether atouch has occurred or not while maintaining the user's finger at apredetermined distance from the sensing areas without contacting them.In this case, as the distance between the sensing areas and the user'sfinger increases, the capacitance of respective sensing areas decreasesnoticeably compared with the finger mode. The present invention isadvantageous in that multiple sensing areas are activated to make itpossible to sufficiently sense whether a touch has occurred or not evenin the hover mode, and the increased capacitance of the total sensingareas improves the sensing capability.

According to the present invention, it is possible to provide a touchsensing device, a touch sensing circuit, and a data driving circuit,which can perform touch driving suitable for each of a contact touch anda non-contact touch.

The additional range of applicability of the present invention willbecome clear from the following detailed description. However, variouschanges and modifications within the idea and scope of the presentinvention can be clearly understood by a person skilled in the art, andit is to be understood that the detailed description and specificembodiments, such as preferred embodiments, of the present invention aregiven only as examples.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will be more apparent from the following detailed descriptiontaken in conjunction with the accompanying drawings, in which:

FIG. 1 is a diagram illustrating a touch sensor having touch sensorsembedded in a display panel according to an embodiment of the presentinvention;

FIG. 2 is a block diagram illustrating a display device according to anembodiment of the present invention;

FIG. 3 is an equivalent circuit diagram of a liquid crystal cell;

FIG. 4 is a waveform diagram of a vertical synchronization signalillustrating a method for time division driving of a display panel and atouch sensor;

FIG. 5 is a diagram illustrating a touch sensing device according to thepresent invention;

FIG. 6 is a diagram illustrating a selection circuit of FIG. 5 indetail;

FIG. 7 is a circuit diagram illustrating a detailed structure of a firstselection circuit of FIG. 6;

FIG. 8 is a waveform diagram for driving a touch sensing device in afinger mode according to the present invention;

FIGS. 9A, 9B, 9C and FIG. 9D are diagrams illustrating finger-modedriving of a touch sensing device according to the present invention;

FIG. 10 is a waveform diagram for driving a touch sensing device in ahover mode according to the present invention;

FIG. 11A and FIG. 11B are diagrams illustrating hover-mode driving of atouch sensing device according to the present invention;

FIG. 12 is a waveform diagram illustrating a driving signal for sensinga display panel in a touch sensing device according to the presentinvention;

FIG. 13 is a diagram illustrating a display device driving modeaccording to the present invention;

FIG. 14 and FIG. 15 are diagrams illustrating driving signals used in adisplay device touch driving mode according to the present invention,respectively;

FIGS. 16A, 16B, 16C and FIG. 16D are exemplary diagrams of drivingsignals in each of a contact touch driving mode and a non-contact touchdriving mode according to the present invention;

FIG. 17 is a driving timing diagram when a frame period proceeds in atime division scheme, i.e. as a display driving period, a contact touchdriving period, and a non-contact touch driving period, during drivingof a display device according to the present invention;

FIG. 18 is a diagram illustrating length-variable characteristics of acontact touch driving period and a non-contact touch driving period whena frame period proceeds in a time division scheme, i.e. as a displaydriving period, a contact touch driving period, and a non-contact touchdriving period, during driving of a display device according to thepresent invention;

FIG. 19 is a driving timing diagram when a frame period is time-dividedinto a display driving period and a touch driving period, during drivingof a display device according to the present invention, and the touchdriving period proceeds as one of a contact touch driving period and anon-contact touch driving period;

FIG. 20 is a diagram illustrating a parasitic capacitor generated duringtouch driving of a display device according to the present invention anda load-free driving scheme for improving touch sensing errors resultingtherefrom;

FIG. 21 and FIG. 22 are diagrams illustrating touch sensing deviceshaving touch sensing circuits included in data driving circuits,respectively, according to the present invention;

FIG. 23 is a diagram illustrating a touch sensing device having two ormore touch sensing circuits included in a data driving circuit accordingto the present invention;

FIG. 24 is a diagram illustrating multiplexer timing in connection witha touch sensing device according to the present invention; and

FIG. 25 is a diagram illustrating the operation of a multiplexer inconnection with a touch sensing device according to the presentinvention.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, embodiments disclosed in the specification will bedescribed in detail with reference to the accompanying drawings, and thesame or similar elements will given the same reference numeralsthroughout the drawings, and repeated descriptions thereof will beomitted herein. The suffixes of component elements used in the followingdescriptions, such as, a “module” and a “unit”, are assigned or usedtogether only for ease of description, but they do not havedistinguishing meanings or roles. Further, in the following descriptionof the present invention, a detailed description of known technologiesincorporated herein will be omitted when it may make the subject matterof the present disclosure rather unclear. In addition, it is to beunderstood that the accompanying drawings are only for betterunderstanding of embodiments disclosed in the specification, and doesnot limit the technical idea disclosed in the specification, andincludes all changes, equivalents, and substitutes included in the ideaand technical scope of the present invention.

A display device according to the present invention provides a touchmode, and the touch mode can be largely divided into a contact touchmode and a non-contact touch mode.

The contact touch mode refers to a mode in which a touch made bydirectly contacting a display panel is recognized, and is also referredto as a finger mode.

The non-contact touch mode refers to a mode in which a touch on thedisplay panel, without directly contacting the same, is recognized, andmay include a proximity touch mode, in which a proximity touch, withoutcontacting the display panel, is recognized, and a hovering mode, inwhich hovering over the display panel is recognized.

In addition, the display device according to the present invention maybe implemented on the basis of a flat panel display device, such as aLiquid Crystal Display (LCD), a Field Emission Display (FED), a PlasmaDisplay Panel (PDP), an Organic Light Emitting Display (OLED), anElectroPhoresis Display (EPD), etc.

It is to be noted that, although the display device will be described inthe following embodiments with reference to an LCD as an example of theflat panel display device, the display device according to the presentinvention is not limited to the LCD.

The LCD according to the present invention may include touch sensors(TS) as illustrated in FIG. 1; that is, the touch sensors (TS) may beembedded in a pixel array of the LCD panel. In FIG. 1, “PIX” refers to apixel electrode of a pixel, “GLS1” refers to an upper substrate, “GLS2”refers to a lower substrate, and “POL2” refers to a lower polarizationplate.

The LCD panel may have multiple pixels arranged thereon. Each pixel mayinclude R, G, B sub-pixels or R, G, B, W sub-pixels, but is not limitedthereto.

The upper substrate GLS1 may include R, G, B color filters correspondingto the sub-pixels of each pixel or may have a color filter layerincluding R, G, B, W color filters.

The touch sensors TS may be arranged on respective pixels or arranged onrespective sub-pixels, but are not limited thereto.

Each pixel may have a thin-film transistor and a pixel electrodearranged thereon, the thin-film transistor making it possible to selecteach pixel, and the pixel electrode being electrically connected to thethin-film transistor.

The touch sensors TS may be capacitive touch sensors TS, which sense achange of capacitance caused by a touch, but are not limited thereto.

The touch sensors TS may sense a change of capacitance resulting notonly from a direct touch with regard to the upper surface of the uppersubstrate GLS1, but also from a non-contact (proximity or hovering) withregard to the upper surface of the upper substrate (GLS1) and maydetermine whether a touch has occurred or not on the basis of the resultof sensing.

As used herein, hovering may refer to a state in which the distance fromthe upper surface of the upper substrate GLS1 is larger than in the caseof proximity.

Display panels including capacitive touch sensors TS are classified intoself-capacitance types and mutual capacitance types. Theself-capacitance is formed along a single layer of conductor wiringformed in one direction. The mutual capacitance is formed between twoperpendicular layers of conductor wiring.

FIG. 2 is a block diagram illustrating a display device according to anembodiment of the present invention, and FIG. 3 is an equivalent circuitdiagram of a liquid crystal cell.

Referring to FIG. 2 and FIG. 3, the display device according to thepresent invention includes a display panel 10, a display panel drivingcircuit, a timing controller 22, and a touch sensing circuit 100.

The display panel 10 may be a self-capacitive display panel of anin-cell type, which has touch sensors TS embedded therein, asillustrated in FIG. 1.

The display panel 10 includes a liquid crystal layer formed between twosubstrates GSL1 and GLS2. The substrates may be fabricated as glasssubstrates, plastic substrates, film substrates, etc. A pixel arrayformed on the lower substrate GLS2 of the display panel 10 includes datalines 11, gate lines 12 extending perpendicular to the data lines 11,and pixels arranged in a matrix type. The pixel array further includesmultiple TFTs (Thin Film Transistors) formed at intersections betweenthe data lines 11 and the gate lines 12, pixel electrodes 1 for chargingthe pixels with a data voltage, storage capacitors Cst connected to thepixel electrodes 1 to maintain the pixel voltage, etc.

The pixels of the display panel 10 are arranged in a matrix defined bythe data lines 11 and the gate lines 12. The liquid crystal cells Clc ofrespective pixels are driven by an electric field applied according tothe voltage difference between a data voltage, which is applied to thepixel electrodes 1, and a common voltage, which is applied to commonelectrodes 2, and adjust the amount of transmission of incident light.The TFTs are turned on in response to a gate pulse from the gate lines12 and supply the pixel electrodes 1 of the liquid crystal cells Clcwith the voltage from the data lines 11. The common electrodes 2 may beformed on the lower substrate GLS2 or the upper substrate GLS1.

The upper substrate GLS1 of the display panel 10 may include a blackmatrix, a color filter, etc. Polarization plates POL1 and POL2 areattached to the upper and lower substrates GLS1 and GLS2 of the displaypanel 10, respectively, and an orientation film (not illustrated) isformed on an inner surface, which contacts the liquid crystal, in orderto set the free tilt angle of the liquid crystal. A spacer (notillustrated) may be formed between the upper and lower substrates GLS1and GLS2 of the display panel 10 in order to maintain the cell gap ofthe liquid crystal cells Clc, but is not limited in any manner.

The display panel 10 may be implemented in any of widely known liquidcrystal modes, such as a TN (Twisted Nematic) mode, a VA (VerticalAlignment) mode, an IPS (In Plane Switching) mode, a FFS (Fringe FieldSwitching) mode, etc.

A backlight unit (not illustrated) may be arranged on the rear surfaceof the display panel 10. The backlight unit is implemented as anedge-type or direct-type backlight unit and emits light to the displaypanel 10.

The display panel driving circuit writes data regarding input images inthe pixels of the display panel 10 using a data driving circuit 24 andgate driving circuits 26 and 30.

The data driving circuit 24 generates a data voltage by convertingdigital video data RGB, which is input from the timing controller 22,using an analog positive/negative gamma compensation voltage. The datadriving circuit 24 supplies the data lines 11 with the data voltageunder the control of the timing controller 22 and reverses the polarityof the data voltage.

The gate driving circuits 26 and 30 successively supply the gate lines12 with a gate pulse (or scan pulse), which is synchronized with thedata voltage, and select a line of the display panel 10 in which thedata voltage is written.

The gate driving circuits include a level shifter 26 and a shiftregister 30. In line with the developing GIP (gate in panel) processtechnology, the shift register 30 may be directly formed on thesubstrate of the display panel 10.

The level shifter 26 may be formed on a printed circuit board(hereinafter, referred to as a PCB) 20 electrically connected to thelower substrate GLS2 of the display panel 10 together with the timingcontroller 22. The level shifter 26 outputs a start pulse VST, whichswings between a gate high voltage VGH and a gate low voltage VGL, andat least one clock signal CLK under the control of the timing controller22. The gate high voltage VGH may be set as a voltage equal to or higherthan the threshold voltage of the TFTs formed in the pixel array of thedisplay panel 10. The gate low voltage VGL may be set as a voltage equalto or lower than the threshold voltage of the TFTs formed in the pixelarray of the display panel 10. The level shifter 26 outputs a startpulse VST and at least one clock signal CLK, which swing between thegate high voltage VGH and the gate low voltage VGL, respectively, inresponse to a start pulse ST, a first clock GCLK, and a second clockMCLK, which are input from the timing controller 22. The at least oneclock signal CLK output from the level shifter 26 successively undergoesphase shift and is transmitted to the shift register 30 formed on thedisplay panel 10.

The shift register 30 may be arranged on an edge of the lower substrateGLS2 of the display panel 10, on which a pixel array is formed, so as tobe connected with the gate lines 12 of the pixel array. The shiftregister 30 may include multiple stages connected subordinately.

The shift register 30 starts operating in response to a start pulse VSTinput from the level shifter 26, shifts output in response to clocksignals CLK, and successively supplies the gate lines 12 of the displaypanel 10 with a gate pulse.

The timing controller 22 may supply the data driving circuit 24 withdigital video data, which is input from an external host system. Thedata driving circuit 24 may be manufactured as an IC (IntegratedCircuit) and mounted on a chip-on-board or a chip-on-film.

The timing controller 22 may receive timing signals input from theexternal host system, such as a vertical synchronization signal Vsync, ahorizontal synchronization signal Hsync, a data enable DE signal, aclock, etc., and generate timing control signals for controlling theoperation timing of the data driving circuit 24 and the gate drivingcircuits 26 and 30. The timing controller 22 or the host systemgenerates a synchronization signal SYNC (refer to FIG. 4) forcontrolling the operation timing of the display panel driving circuitand the touch sensing circuit 100.

The touch sensing circuit 100 may apply a driving signal to wiringsconnected to the touch sensors TS and count the change in driving signalvoltage before and after the touch or the rising or falling edge delaytime of the driving signal, thereby sensing the change in capacitancebefore and after input of the touch (or proximity). The touch sensingcircuit 100 converts a voltage received from the touch sensors TS intodigital data, thereby generates touch raw data, executes a preset touchrecognition algorithm, analyzes the touch raw data, and detects a touch(or proximity) input. The touch sensing circuit 100 transmits touchreport data, including coordinates of touch (or proximity) inputpositions, to the host system.

The host system may be implemented as one of a navigation system, aset-top box, a DVD player, a Blue ray player, a PC, a home theatersystem, a broadcast receiver, and a phone system. The host systemconverts digital video data regarding input images into a format, whichconforms to the resolution of the display panel 10, using a scaler andtransmits the data and a timing signal to the timing controller 22. Inaddition, the host system executes an application program associatedwith a touch (or proximity) input in response to the touch report datainput from the touch sensing circuit 100.

The display 10, which has touch sensors TS embedded therein, and thetouch sensing circuit 100 may be time-division-driven according to amethod as illustrated in FIG. 4. One frame period, as illustrated inFIG. 4, may be time-divided into a display panel driving period T1 and atouch driving period T2.

In FIG. 4, “Vsync” refers to a first vertical synchronization signalinput to the timing controller 22, and “SYNC” refers to a secondvertical synchronization signal input to the touch sensing circuit 100.The timing controller 22, in order to define a display panel drivingperiod T1 and a touch driving period T2 in one frame period, maymodulate the first vertical synchronization signal Vsync input from thehost system and thereby generate a second vertical synchronizationsignal SYNC. In a different embodiment, the host system may generate asecond vertical synchronization signal SYNC as illustrated in FIG. 4,and the timing controller 22 may control the display panel drivingperiod T1 and the touch driving period T2 in response to the secondvertical synchronization signal SYNC input from the host system.Therefore, according to the present invention, one frame period may betime-divided into a display panel driving period T1 and a touch drivingperiod T2 such that, as a controller that controls the operation timingof the display panel driving circuit and the touch sensing circuit 100,one of the timing controller 22 and the host system may be used.

The display panel driving period T1 may be defined in the low logiclevel section of the second vertical synchronization signal SYNC, andthe touch driving period T2 may be defined in the high logic levelsection of the second vertical synchronization signal SYNC, but thepresent invention is not limited thereto. For example, the display paneldriving period T1 may be defined in the high logic level section of thesecond vertical synchronization signal SYNC, and the touch drivingperiod T2 may be defined in the low logical level section of the secondvertical synchronization signal SYNC.

During the display panel driving period T1, the display panel drivingcircuit is driven, while the touch sensing circuit 100 is not driven.During the display panel driving period T1, the data driving circuit 24supplies the data lines 11 with a data voltage under the control of thetiming controller 22, and the gate driving circuits 26 and 30successively supplies the gate lines 12 with a gate pulse. The touchsensing circuit 100, during the display panel driving period T1, doesnot supply the touch sensors TS of the display panel 10 with a drivingsignal.

During the touch driving period T2, the display panel driving circuit isnot driven, while the touch sensing circuit 100 is driven. The touchsensing circuit 100 applies a driving signal to the touch sensors TSwithin the touch driving period T2.

Touch sensors TS in sensing areas 111, 112, 113, 114, 115, and 116 (FIG.5) may be connected to sensing lines 121, 122, 123, 124, 125, and 126(FIG. 5). For example, sensing lines 121, 122, 123, 124, 125, and 126may be arranged in parallel with gate lines 12, but are not limitedthereto.

One touch sensor may be formed in each sensing area, or multiple touchsensors may be formed in each sensing area.

Each sensing area may correspond to multiple pixels, but the presentinvention is not limited thereto. One touch sensor may be formed in eachpixel, or one touch sensor may be formed in multiple pixels.

An in-cell-type touch display panel 10, which has touch sensors TSembedded in the display panel 10 as illustrated in FIG. 1, is moresensitively influenced by variation of load of the display panel orchange in parasitic capacitance, compared with a scheme in which touchsensors TS are attached on the display panel.

Hereinafter, the wiring structure of an in-cell-type display panel 10and a method for driving the same will be described.

FIG. 5 is a diagram illustrating a touch sensing device according to thepresent invention, and FIG. 6 is a diagram illustrating a selectioncircuit of FIG. 5 in detail.

The touch sensing device illustrated in FIG. 5 may be a part of thedisplay device illustrated in FIG. 2.

Referring to FIG. 5, the touch sensing device according to the presentinvention may include an in-cell-type, self-capacitive display panel 10.

The display panel 10 may include multiple sensing areas 111 to 116.Respective sensing area 111 to 116 may be made of a transparentconductive material, such as ITO, but the present invention is notlimited thereto. Respective sensing area 111 to 116 may be arranged onthe same layer as the pixel electrodes 1, for example, but the presentinvention is not limited thereto.

Respective sensing areas 111 to 116 may be connected to the touchsensors TS illustrated in FIG. 1.

The size of respective sensing areas 111 to 116 may be at least largerthan the pixel size. In other words, the size of one sensing area maycorrespond to the entire size of multiple pixels. For example,respective sensing area 111 to 116 may correspond to at least threepixels, but the present invention is not limited thereto. That is, onesensing area may be defined with regard to at least three pixels. Thenumber of pixels, the entire size of which corresponds to the size ofone sensing area, can be optimized through experiments.

Respective sensing areas 111 to 116 may be used as touch electrodesduring the touch driving period T2, for example, and used as commonelectrodes during the display panel driving period T1, for example.

The touch sensing circuit 100 may be disabled during the display paneldriving period T1 and enabled during the touch driving period T2,thereby supplying sensing areas 111 to 116 with a driving signal (referto FIG. 12) via sensing lines 121, 122, 123, 124, 125, and 126 duringthe touch driving period T2.

A common voltage generated by a common voltage generation unit (notillustrated) may be supplied to the sensing areas 111 to 116 via thesensing lines 121, 122, 123, 124, 125, and 126 during the display paneldriving period T1. Therefore, images can be displayed on the displaypanel 10 by means of a liquid crystal displacement resulting from thedifference in electric potential between the common voltage supplied tothe sensing areas 111 to 116 and the data voltage supplied to the pixelelectrodes 1.

During the touch driving period T2, driving signals S1 to S4 (refer toFIG. 12) generated from the touch sensing circuit 100 may be supplied tothe sensing areas 111 to 116. As a result, corresponding sensing areas111 to 116 are activated; and, when a touch regarding the correspondingsensing areas 111 to 116 is input from the user, the capacitanceconnected to the corresponding sensing areas 111 to 116 is changed, anda sensing signal, which occurs as the changed capacitance is reflectedin the driving signals S1 to S4, may be detected and provided to thetouch sensing circuit 100.

A sensing area including at least one touch sensor TS may beelectrically connected to a corresponding sensing line.

Driving signals S1 to S4, as illustrated in FIG. 12, are supplied to thesensing areas 111 to 116 via the sensing lines 121, 122, 123, 124, 125,and 126, and a change of capacitance, which occurs according to whetherthe user touches the sensing areas 111 to 116 or not, is provided to thetouch sensing circuit 100 via the sensing lines 121, 122, 123, 124, 125,and 126, thereby enabling touch recognition.

Multiple sensing areas 111 to 116 may be distinguished by multiplesensing area blocks 170, 180, and 190. For example, multiple sensingareas 111 to 116 arranged along the longitudinal direction of thesensing lines 121, 122, 123, 124, 125, and 126 may be defined as onesensing area block.

In this case, first to sixth sensing area blocks 170 a, 180 a, 190 a,170 b, 180 b, and 190 b may be provided as illustrated in FIG. 5.Although six sensing blocks 170 a, 180 a, 190 a, 170 b, 180 b, and 190b, each of which includes four sensing areas, are illustrated in FIG. 5for convenience of description, more than six sensing area blocks, eachof which includes more than four sensing areas, may be includedaccording to the present invention.

As illustrated in FIG. 5, the first sensing area block 170 a may includefour sensing areas 111 a, 111 b, 111 c, and 111 d, and respectivesensing areas 111 a, 111 b, 111 c, and 111 d may be connected tocorresponding sensing lines 121 a, 121 b, 121 c, and 121 d.

On the other hand, the touch sensing circuit 100 may include a sensingsignal detection unit 104 and a selection circuit 102.

The sensing signal detection unit 104 may supply driving signals S1 toS4, illustrated in FIG. 12, to respective sensing area blocks 170 a, 180a, 190 a, 170 b, 180 b, and 190 b on the display panel 10 or torespective sensing areas 111 to 116 and receive sensing signalsresulting from sensing by respective sensing area blocks 170 a, 180 a,190 a, 170 b, 180 b, and 190 b or by respective sensing areas 111 to116.

The selection circuit 102 may successively select multiple sensing areas111 to 116 included in respective sensing area blocks 170 a, 180 a, 190a, 170 b, 180 b, and 190 b or simultaneously select at least two sensingareas from multiple sensing areas 111 to 116 included in respectivesensing area blocks 170 a, 180 a, 190 a, 170 b, 180 b, and 190 b.

For example, in the case of a finger mode, the selection circuit 102 mayselect a first sensing area 111 a included in a first sensing area block170 a during the first period of the touch driving period T2 and mayselect a second sensing area 111 b included in the first sensing areablock 170 a during the second period of the touch driving period T2.Thereafter, the selection circuit 102 may select a third sensing area111 c included in the first sensing area block 170 a during the thirdperiod of the touch driving period T2 and may select a fourth sensingarea 111 d included in the first sensing area block 170 a during thefourth period of the touch driving period T2. After all sensing areas111 a, 111 b, 111 c, and 111 d inside the first sensing area block 170 ahave been selected successively, all sensing areas 112 a, 112 b, 112 c,and 112 d included in the second sensing area block 180 a may beselected successively. In this manner, all sensing areas 113 a to 113 d,114 a to 114 d, 115 a to 115 d, and 116 a to 116 d included in the thirdto sixth sensing area blocks 190 a, 170 b, 180 b, and 190 b may beselected successively by the selection circuit 102.

A sensing signal may be detected, during a period selected by theselection circuit 102, from the corresponding sensing area and providedto the sensing signal detection unit 104.

In the case of a hover mode, for example, the selection circuit 102 mayselect, during the first period of the touch driving period T2, firstand second sensing areas 111 a and 111 b included in the first sensingarea block 170 a, first and second sensing areas 112 a and 112 bincluded in the second sensing area block 180 a, and first and secondsensing areas 113 a and 113 b included in the third sensing area block190 a. Thereafter, the selection circuit 102 may select, during thesecond period of the touch driving period T2, third and fourth sensingareas 111 c and 111 d included in the first sensing area block 170 a,third and fourth sensing areas 112 c and 112 d included in the secondsensing area block 180 a, and third and fourth sensing areas 113 c and113 d included in the third sensing area block 190 a. In this manner,multiple sensing areas 114 a to 114 d, 115 a to 115 d, and 116 a to 116d included in the fourth to sixth sensing area blocks 170 b, 180 b, and190 b may be selected by the selection circuit 102.

As illustrated in FIG. 6, the sensing signal detection unit 104 mayinclude first and second sensing signal detection units 104 a and 104 b.The selection circuit 102 may include first and second selectioncircuits 102 a and 102 b. Each of the first and second selectioncircuits 102 a and 102 b may be a multiplexer, for example, but thepresent invention is not limited thereto.

Although it has been assumed for convenience of description that twosensing signal detection units 104 and two selection circuits 102 areprovided, more than two sensing signal detection units and more than twoselection circuits may also be provided.

In order to reduce the number of output pins of the sensing signaldetection unit 104, first and second selection circuits 102 a and 102 bmay be installed between the sensing signal detection unit 104 and thedisplay panel 10.

Each of the first and second selection circuits 102 a and 102 b is a 1:N(N is a positive integer equal to or larger than 2 and smaller than n, nis the number of sensing lines) multiplexer, and can reduce the numberof pins of the sensing signal detection unit 104 by 1/N.

The output end of the first sensing signal detection unit 104 a may beconnected to the input end of the first selection circuit 102 a. Theoutput end of the second sensing signal detection unit 104 b may beconnected to the input end of the second selection circuit 102 b.

For example, first to fourth output lines 131 a, 131 b, 131 c, and 131 dmay be arranged between the first sensing signal detection unit 104 aand the first selection circuit 102 a, and first to fourth output lines132 a, 132 b, 132 c, and 132 d may be arranged between the secondsensing signal detection unit and the second selection circuit 102 b.For example, first ends of the first to fourth output lines 131 a, 131b, 131 c, and 131 d may be connected to the output end of the firstsensing signal detection unit 104 a, and second ends of the first tofourth output lines 131 a, 131 b, 131 c, and 131 d may be connected tothe input end of the first selection circuit 102 a. For example, firstends of the first to fourth output lines 132 a, 132 b, 132 c, and 132 dmay be connected to the output end of the second sensing signaldetection unit, and second ends of the first to fourth output lines 132a, 132 b, 132 c, and 132 d may be connected to the input end of thesecond selection circuit 102 b.

The output end of the first selection circuit 102 a may be connected tosensing lines 121 a to 121 d, 122 a to 122 d, and 123 a to 123 dincluded in first to third sensing area blocks 170 a, 180 a, and 190 a,and the output end of the second selection circuit 102 b may beconnected to sensing lines 124 a to 124 d, 125 a to 125 d, and 126 a to126 d included in fourth to sixth sensing area blocks 170 b, 180 b, and190 b.

For example, in the case of a finger mode, first to fourth output lines131 a, 131 b, 131 c, and 131 d connected to the input end of the firstselection circuit 102 a may be successively connected, one to one, tofirst to fourth sensing lines 121 a to 121 d included in the firstsensing area block 170 a connected to the output end of the firstselection circuit 102 a, to first to fourth sensing lines 122 a to 122 dincluded in the second sensing area block 180 a, or to first to fourthsensing lines 123 a to 123 d included in the third sensing area block190 a. Similarly, in the case of a finger mode, first to fourth outputlines 132 a, 132 b, 132 c, and 132 d connected to the input end of thesecond selection circuit 102 b may be successively connected, one toone, to first to fourth sensing lines 124 a to 124 d included in thefourth sensing area block 170 b connected to the output end of thesecond selection circuit 102 b, to first to fourth sensing lines 125 ato 125 d included in the fifth sensing area block 180 b, or to first tofourth sensing lines 126 a to 126 d included in the sixth sensing areablock 190 b.

For example, in the case of a hover mode, the first output line 131 aconnected to the input end of the first selection circuit 102 a may besimultaneously connected to first sensing lines 121 a, 122 a, and 123 aincluded in the first to third sensing area blocks 170 a, 180 a, and 190a, respectively, which are connected to the output end of the firstselection circuit 102 a, and the second output line 131 b connected tothe input end of the first selection circuit 102 a may be simultaneouslyconnected to second sensing lines 121 b, 122 b, and 123 b included inthe first to third sensing area blocks 170 a, 180 a, and 190 a,respectively, which are connected to the output end of the firstselection circuit 102 a. For example, in the case of a hover mode, thefirst output line 132 a connected to the input end of the secondselection circuit 102 b may be simultaneously connected to first sensinglines 124 a, 125 a, and 126 a included in the fourth to sixth sensingarea blocks 170 b, 180 b, and 190 b, respectively, which are connectedto the output end of the second selection circuit 102 b, and the secondoutput line 132 b connected to the input end of the second selectioncircuit 102 b may be simultaneously connected to second sensing lines124 b, 125 b, and 126 b included in the fourth to sixth sensing areablocks 170 b, 180 b, and 190 b, respectively, which are connected to theoutput end of the second selection circuit 102 b.

As illustrated in FIG. 7, the first selection circuit 102 a may includefirst to third switch groups 140, 150, and 160.

For example, the output end of the first switch group 140 may beconnected to the first to fourth sensing lines 121 a to 121 d of thefirst sensing area block 170 a. For example, the output end of thesecond switch group 150 may be connected to the first to fourth sensinglines 122 a to 122 d of the second sensing area block 180 a. Forexample, the output end of the third switch group 160 may be connectedto the first to fourth sensing lines 123 a to 123 d of the third sensingarea block 190 a.

For example, the first switch group 140 may connect the first to fourthoutput lines 131 a, 131 b, 131 c, and 131 d, which are connected to theoutput end of the first sensing signal detection unit 104 a, to thefirst to fourth sensing lines 121 a to 121 d of the first sensing areablock 170 a, respectively.

For example, the second switch group 150 may connect the first to fourthoutput lines 131 a, 131 b, 131 c, and 131 d, which are connected to theoutput end of the first sensing signal detection unit 104 a, to thefirst to fourth sensing lines 122 a to 122 d of the second sensing areablock 180 a, respectively.

For example, the third switch group 160 may connect the first to fourthoutput lines 131 a, 131 b, 131 c, and 131 d, which are connected to theoutput end of the first sensing signal detection unit 104 a, to thefirst to fourth sensing lines 123 a to 123 d of the third sensing areablock 190 a, respectively.

For example, the first switch group 140 may include first to fourthswitches 142, 144, 146, and 148. The first to fourth switches 142, 144,146, and 148 may be semiconductor transistors, but the present inventionis not limited thereto. The first switch 142 may be connected betweenthe first output line 131 a and the first sensing line 121 a of thefirst sensing area block 170 a. The second switch 144 may be connectedbetween the second output line 131 b and the second sensing line 121 bof the first sensing area block 170 a. The third switch 146 may beconnected between the third output line 131 c and the third sensing line121 c of the first sensing area block 170 a. The fourth switch 148 maybe connected between the fourth output line 131 d and the fourth sensingline 121 d of the first sensing area block 170 a.

Similarly, the second switch group 150 may include first to fourthswitches 152, 154, 156, and 158, and the third switch group 160 mayinclude first to fourth switches 162, 164, 166, and 168.

On the other hand, although not illustrated, the detailed structure ofthe second selection circuit 102 b is substantially identical to thedetailed structure of the first selection circuit 102 a, and thedetailed structure of the second selection circuit 102 b therefore canbe easily understood from that of the first selection circuit 102 a,repeated description thereof being omitted herein for clarity.

The touch sensing device including the selection circuit 102 configuredas above can be driven differently according to a finger mode and ahover mode. In the case of the finger mode, the selection circuit 102may be driven by selection signals S11, S21, S31, and S41 illustrated inFIG. 8; and, in the case of the hover mode, the selection circuit 102may be driven by selection signals S12 and S22 illustrated in FIG. 10.The selection signals illustrated in FIG. 8 and FIG. 10 are examplesonly, and various variants are possible.

Finger Mode Driving

A method for driving in the finger mode, in connection with a touchsensing device, will be described with reference to FIGS. 5 to 8, 9A,9B, 9C, and 9D.

FIG. 8 is a waveform diagram for driving in the finger mode inconnection with a touch sensing device according to the presentinvention, and FIGS. 9A, 9B, 9C, and 9D are diagrams illustrating fingermode driving in connection with the touch sensing device according tothe present invention.

As illustrated in FIG. 8, first to fourth selection signals S11, S21,S31, and S41 may be supplied to the first selection circuit 102 a.Specifically, the first selection signal S11 may be supplied to thefirst switches 142, 152, and 162 of the first to third switch groups140, 150, and 160, respectively, such that the first switches 142, 152,and 162 can be switching-controlled in response to the first selectionsignal S11. The second selection signal S21 may be supplied to thesecond switches 144, 154, and 164 of the first to third switch groups140, 150, and 160, respectively, such that the second switches 144, 154,and 164 can be switching-controlled in response to the second selectionsignal S21. The third selection signal S31 may be supplied to the thirdswitches 146, 156, and 166 of the first to third switch groups 140, 150,and 160, respectively, such that the third switches 146, 156, and 166can be switching-controlled in response to the third selection signalS31. The fourth selection signal S41 may be supplied to the fourthswitches 148, 158, and 168 of the first to third switch groups 140, 150,and 160, respectively, such that the fourth switches 148, 158, and 168can be switching-controlled in response to the fourth selection signalS41.

More specifically, the first selection signal S11 may include first tothird pulses P11, P12, and P13, which have high levels. The first pulseP11 may be supplied to the first switch 142 of the first switch group140, the second pulse P12 may be supplied to the first switch 152 of thesecond switch group 150, and the third pulse P13 may be supplied to thefirst switch 162 of the third switch group 160.

The second selection signal S21 may include first to third pulses P21,P22, and P23, which have high levels. The first pulse P21 may besupplied to the second switch 144 of the first switch group 140, thesecond pulse P22 may be supplied to the second switch 154 of the secondswitch group 150, and the third pulse P23 may be supplied to the secondswitch 164 of the third switch group 160.

The third selection signal S31 may include first to third pulses P31,P32, and P33, which have high levels. The first pulse P31 may besupplied to the third switch 146 of the first switch group 140, thesecond pulse P32 may be supplied to the third switch 156 of the secondswitch group 150, and the third pulse P33 may be supplied to the thirdswitch 166 of the third switch group 160.

The fourth selection signal S41 may include first to third pulses P41,P42, and P43, which have high levels. The first pulse P41 may besupplied to the fourth switch 148 of the first switch group 140, thesecond pulse P42 may be supplied to the fourth switch 158 of the secondswitch group 150, and the third pulse P43 may be supplied to the fourthswitch 168 of the fourth switch group.

As illustrated in FIG. 8, the first pulse P11 of the first selectionsignal S11, the first pulse P21 of the second selection signal S21, thefirst pulse P31 of the third selection signal S31, and the first pulseP41 of the fourth selection signal P41 may be generated successively,and the first to fourth switches 142, 144, 146, and 148 of the firstswitch group 140 may be turned on successively by the first pulse P11 ofthe first selection signal S11, the first pulse P21 of the secondselection signal S21, the first pulse P31 of the third selection signalS31, and the first pulse P41 of the fourth selection signal P41, whichhave been generated successively.

The second pulse P12 of the first selection signal S11, the second pulseP22 of the second selection signal S21, the second pulse P32 of thethird selection signal S31, and the second pulse P42 of the fourthselection signal P41 may be generated successively, and the first tofourth switches 152, 154, 156, and 158 of the second switch group 150may be turned on by the second pulse P12 of the first selection signalS11, the second pulse P22 of the second selection signal S21, the secondpulse P32 of the third selection signal S31, and the second pulse P42 ofthe fourth selection signal P41, which have been generated successively.

The third pulse P13 of the first selection signal S11, the third pulseP23 of the second selection signal S21, the third pulse P33 of the thirdselection signal S31, and the third pulse P43 of the fourth selectionsignal P41 may be generated successively, and the first to fourthswitches 162, 164, 166, and 168 of the third switch group 160 may beturned on by the third pulse P13 of the first selection signal S11, thethird pulse P23 of the second selection signal S21, the third pulse P33of the third selection signal S31, and the third pulse P43 of the fourthselection signal P41, which have been generated successively.

As illustrated in FIG. 9A, the first switch 142 of the first switchgroup 140 may be turned on in response to the first pulse P11 of thefirst selection signal S11, and the first driving signal S1 illustratedin FIG. 12 may be supplied to the first sensing area 111 a of the firstsensing area block 170 a via the first switch 142 of the first switchgroup 140 and the first sensing line 121 a. As a result, the firstsensing area 111 a of the first sensing area block 170 a is activated,and a sensing signal, which reflects a change in capacitance as a resultof the user's touch input with regard to the first sensing area 111 a,may be supplied to the first sensing signal detection unit 104 a via thefirst sensing line 121 a and the first switch 142. In this case, thesecond to fourth switches 144, 146, and 148 are turned off.

As illustrated in FIG. 9B, the second switch 144 of the first switchgroup 140 may be turned on in response to the first pulse P21 of thesecond selection signal S21, and the second driving signal S21illustrated in FIG. 12 may be supplied to the second sensing area 111 bof the first sensing area block 170 a via the second switch 144 of thefirst switch group 140 and the second sensing line 121 b. As a result,the second sensing area 111 b of the first sensing area block 170 a isactivated, and a sensing signal, which reflects a change in capacitanceas a result of the user's touch input with regard to the second sensingarea 111 b, may be supplied to the first sensing signal detection unit104 a via the second sensing line 121 b and the second switch 144. Inthis case, the first, third, and fourth switches 142, 146, and 148 areturned off.

As illustrated in FIG. 9C, the third switch 146 of the first switchgroup 140 may be turned on in response to the first pulse P31 of thethird selection signal S31, and the third driving signal S3 illustratedin FIG. 12 may be supplied to the third sensing area 111 c of the firstsensing area block 170 a via the third switch 146 of the first switchgroup 140 and the third sensing line 121 c. As a result, the thirdsensing area 111 c of the first sensing area block 170 a is activated,and a sensing signal, which reflects a change in capacitance as a resultof the user's touch input with regard to the third sensing area 111 c,may be supplied to the first sensing signal detection unit 104 a via thethird sensing line 121 c and the third switch 146. In this case, thefirst, second, and fourth switches 142, 144, and 148 are turned off.

As illustrated in FIG. 9D, the fourth switch 148 of the first switchgroup 140 may be turned on in response to the first pulse P41 of thefourth selection signal S41, and the fourth driving signal S4illustrated in FIG. 12 may be supplied to the fourth sensing area 111 dof the first sensing area block 170 a via the fourth switch 148 of thefirst switch group 140 and the fourth sensing line 121 d. As a result,the fourth sensing area 111 d of the first sensing area block 170 a isactivated, and a sensing signal, which reflects a change in capacitanceas a result of the user's touch input with regard to the fourth sensingarea 111 d, may be supplied to the first sensing signal detection unit104 a via the fourth sensing line 121 d and the fourth switch 148. Inthis case, the first to third switches 142, 144, and 146 are turned off.

Although not illustrated, the second pulse P12 of the first selectionsignal S11, the second pulse P22 of the second selection signal S21, thesecond pulse P32 of the third selection signal S31, and the second pulseP42 of the fourth selection signal S41 are successively supplied suchthat the first to fourth switches 152, 154, 156, and 158 of the secondswitch group 150 are turned on successively; as a result, a sensingsignal, which reflects whether the user touches the first to fourthsensing areas 112 a to 112 d of the second sensing area block 180 a ornot, may be supplied to the first sensing signal detection unit 104 a.

Although not illustrated, the third pulse P13 of the first selectionsignal S11, the third pulse P23 of the second selection signal S21, thethird pulse P33 of the third selection signal S31, and the third pulseP43 of the fourth selection signal S41 are successively supplied suchthat the first to fourth switches 162, 164, 166, and 168 of the thirdswitch group 160 are turned on successively; as a result, a sensingsignal, which reflects whether the user touches the first to fourthsensing areas 113 a to 113 d of the third sensing area block 190 a ornot, may be supplied to the first sensing signal detection unit 104 a.

Although not illustrated, the selection signals S11, S21, S31, and S41illustrated in FIG. 8 may be supplied to the second selection circuit102 b as well. As a result, the second selection circuit 102 b may alsobe selectively driven by the selection signals S11, S21, S31, and S41illustrated in FIG. 8 in the same manner as the selective driving of thefirst selection circuit 102 a describe above.

As described above, multiple sensing areas 111 a to 111 d, 112 a to 112d, and 113 a to 113 d in respective sensing area blocks 170 a, 180 a,and 190 a may be activated successively in the finger mode. In thefinger mode, a direct contact occurs between the user and the sensingareas 111 a to 111 d, 112 a to 112 d, and 113 a to 113 d, and thedistance between the sensing areas 111 a to 111 d, 112 a to 112 d, and113 a to 113 d and the user's finger becomes zero. As result, thecapacitance of respective sensing areas 111 a to 111 d, 112 a to 112 d,and 113 a to 113 d is sufficiently large, and it is possible tosufficiently detect whether the user's touch occurs or not throughrespective sensing areas 111 a to 111 d, 112 a to 112 d, and 113 a to113 d.

Hover Mode Driving

A method for driving in the hover mode, in connection with a touchsensing device, will be described with reference to FIG. 5 to FIG. 7 andFIG. 10, FIG. 11A, and FIG. 11B.

FIG. 10 is a waveform diagram for driving in the hover mode inconnection with a touch sensing device according to the presentinvention, and FIG. 11A and FIG. 11B are diagrams illustrating hovermode driving in connection with the touch sensing device according tothe present invention.

As illustrated in FIG. 10, two selection signals S12 and S22 may begenerated successively, and first to fourth switches 142-148, 152-158,and 162-168 of first to third switch groups 140, 150, and 160 includedin the first selection circuit 102 a may be switching-controlled by thetwo selection signals S12 and S22.

For example, the first selection signal S12 may be simultaneouslysupplied to the first and second switches 142 and 144 of the firstswitch group 140, to the first and second switches 152 and 154 of thesecond switch group 150, and to the first and second switches 162 and164 of the third switch group 160 such that the first and secondswitches 142 and 144 of the first switch group 140, the first and secondswitches 152 and 154 of the second switch group 150, and the first andsecond switches 162 and 164 of the third switch group 160 can beswitching-controlled simultaneously. The second selection signal S22 maybe simultaneously supplied to the third and fourth switches 146 and 148of the first switch group 140, to the third and fourth switches 156 and158 of the second switch group 150, and to the third and fourth switches166 and 168 of the third switch group 160 such that the third and fourthswitches 146 and 148 of the first switch group 140, the third and fourthswitches 156 and 158 of the second switch group 150, and the third andfourth switches 166 and 168 of the third switch group 160 can beswitching-controlled simultaneously.

As illustrated in FIG. 11A, the first selection signal S12 may besimultaneously supplied to the first to third switch groups 140, 150,and 160 of the first selection circuit 102 a. In response to the firstselection switch S12, the first and second switches 142 and 144 of thefirst switch group 140, the first and second switches 152 and 154 of thesecond switch group 150, and the first and second switches 162 and 164of the third switch group 160 may be turned on simultaneously. As aresult, the first and second driving signals S1 and S2 illustrated inFIG. 12 may be supplied to the first and second sensing areas 111 a, 111b, 112 a, 112 b, 113 a, and 113 b of the first to third sensing areablocks 170 a, 180 a, and 190 a, respectively, via the first and secondswitches 142 and 144 of the first switch group 140, the first and secondswitches 152 and 154 of the second switch group 150, and the first andsecond switches 162 and 164 of the third switch group 160. In this case,a first hover activation block 200 a may be defined as a result ofsimultaneous activation of the first and second sensing areas 111 a, 111b, 112 a, 112 b, 113 a, and 113 b of the first to third sensing areablocks 170 a, 180 a, and 190 a, respectively, via the first and secondswitches 142 and 144 of the first switch group 140, the first and secondswitches 152 and 154 of the second switch group 150, and the first andsecond switches 162 and 164 of the third switch group 160. The firsthover activation block 200 a has six activated sensing areas; as aresult, the total sum of capacitances connected to respective sensingareas accumulates and becomes six times the capacitance of a singlesensing area, and the sensing sensitivity also increases six times; thismakes it possible to easily detect whether the user's touch occurs ornot even in the hover mode, in which the user makes no direct contactwith the display panel 10.

A sensing signal, which reflects whether the user's indirect touchoccurs or not in the hover mode on the basis of improved touchsensitivity of the first hover activation block 200 a, may be suppliedto the first sensing signal detection unit 104 a.

As illustrated in FIG. 11B, the second selection signal S22 may besimultaneously supplied to the first to third switch groups 140, 150,and 160 of the first selection circuit 102 a. In response to the secondselection switch S22, the third and fourth switches 146 and 148 of thefirst switch group 140, the third and fourth switches 156 and 158 of thesecond switch group 150, and the third and fourth switches 166 and 168of the third switch group 160 may be turned on simultaneously. As aresult, the third and fourth driving signals S3 and S4 illustrated inFIG. 12 may be supplied to the third and fourth sensing areas 111 c, 111d, 112 c, 112 d, 113 c, and 113 d of the first to third sensing areablocks 170 a, 180 a, and 190 a, respectively, via the third and fourthswitches 146 and 148 of the first switch group 140, the third and fourthswitches 156 and 158 of the second switch group 150, and the third andfourth switches 166 and 168 of the third switch group 160. In this case,a second hover activation block 200 b may be defined as a result ofsimultaneous activation of the third and fourth sensing areas 111 c, 111d, 112 c, 112 d, 113 c, and 113 d of the first to third sensing areablocks 170 a, 180 a, and 190 a, respectively, via the third and fourthswitches 146 and 148 of the first switch group 140, the third and fourthswitches 156 and 158 of the second switch group 150, and the third andfourth switches 166 and 168 of the third switch group 160. The secondhover activation block 200 b has six activated sensing areas; as aresult, the total sum of capacitances connected to respective sensingareas accumulates and becomes six times the capacitance of a singlesensing area, and the sensing sensitivity also increases six times; thismakes it possible to easily detect whether the user's touch occurs ornot even in the hover mode, in which the user makes no direct contactwith the display panel 10.

Respective hover activation blocks 200 a and 200 b may be at least twosensing areas activated simultaneously.

Although not illustrated, respective hover activation blocks 200 a and200 b may be defined as a first sensing area block 170 a. For example,first to fourth sensing areas 111 a to 111 d within the first sensingarea block 170 a may be defined as a first hover activation block andactivated simultaneously. Thereafter, first to fourth sensing areas 112a to 112 d within the second sensing area block 180 a may be defined asa second hover activation block and activated simultaneously.Thereafter, first to fourth sensing areas 113 a to 113 d within thethird sensing area block 190 a may be defined as a third hoveractivation block and activated simultaneously.

Although not illustrated, the same hover mode driving scheme by means ofdriving of the first selection circuit 102 a illustrated in FIG. 11A andFIG. 11B may be applied to the hover driving scheme by means of drivingof the second selection circuit 102 b.

Although not illustrated, four selection signals may be generatedsuccessively, unlike FIG. 10, and first switches 142, 152, and 162 offirst to third switch groups 140, 150, and 160, respectively, may beturned on simultaneously by the first selection signal such that drivingsignals simultaneously activate the first sensing areas 111 a, 112 a,and 113 a via the first switches 142, 152, and 162 of the first to thirdswitch groups 140, 150, and 160, respectively, and corresponding sensinglines 121 a, 122 a, and 123 a. Second switches 144, 154, and 164 of thefirst to third switch groups 140, 150, and 160, respectively, may beturned on simultaneously by the second selection signal such thatdriving signals simultaneously active the second sensing areas 111 b,112 b, and 113 b via the second switches 144, 154, and 164 of the firstto third switch groups 140, 150, and 160, respectively, andcorresponding sensing lines 121 b, 122 b, and 123 b. Third switches 146,156, and 166 of the first to third switch groups 140, 150, and 160,respectively, may be turned on simultaneously by the third selectionsignal such that driving signals simultaneously active the third sensingareas 111 c, 112 c, and 113 c via the third switches 146, 156, and 166of the first to third switch groups 140, 150, and 160, respectively, andcorresponding sensing lines 121 c, 122 c, and 123 c. Fourth switches148, 158, and 168 of the first to third switch groups 140, 150, and 160,respectively, may be turned on simultaneously by the fourth selectionsignal such that driving signals simultaneously active the fourthsensing areas 111 d, 112 d, and 113 d via the fourth switches 148, 158,and 168 of the first to third switch groups 140, 150, and 160,respectively, and corresponding sensing lines 121 d, 122 d, and 123 d.

In the above-mentioned hover mode, it is detected whether a touch occursor not while the user's finger maintains a predetermined distance fromthe sensing areas 111 a to 1113, 112 a to 112 d, and 131 a to 113 dwithout contacting them. In this case, the capacitance of respectivesensing areas 111 a to 111 d, 112 a to 112 d, and 113 a to 113 ddecreases remarkably as the distance between the sensing areas 111 a to111 d, 112 a to 112 d, and 113 a to 113 d and the user's fingerincreases, compared with the finger mode. According to the presentinvention, multiple sensing areas are activated to make it possible tosufficiently sense whether a touch has occurred or not even in the hovermode, and the increased capacitance of the total sensing areas improvesthe sensing capability.

In addition, according to the present invention, both a finger mode anda sensing mode can be driven such that touch detection is possible notonly by a direct touch by the user, but also by an indirect touch, i.e.non-contact touch, thereby expanding the range of use of the touchsensing device.

Hereinafter, the above-described touch driving scheme will be describedagain briefly, examples of driving signals for the contact touch drivingand the non-contact touch driving will be described, and a load-freedriving scheme for improving the touch sensing accuracy by removing anyunnecessary parasitic capacitance will be described.

A display device according to the present invention provides a touchmode, and the touch mode can be largely divided into a contact touchmode and a non-conact touch mode.

The contact touch mode refers to a mode in which a touch made bydirectly contacting a display panel is recognized, and is also referredto as a finger mode.

The non-contact touch mode refers to a mode in which a touch on thedisplay panel, without directly contacting the same, is recognized, andmay include a proximity touch mode, in which a proximity touch, withoutcontacting the display panel, is recognized, and a hovering mode, inwhich a touch made by hovering over the display panel is recognized.

A touch sensing device according to the present invention includes adisplay panel 10, which includes multiple touch sensors TS, a touchsensing circuit 100, which drives the multiple touch sensors TS andsenses a touch, etc.

The touch sensing circuit 100 may include a sensing signal detectionunit 104, which supplies the multiple touch sensors TS with drivingsignals for touch recognition, and which detects a sensing signalthrough the multiple touch sensors TS, a selection circuit 102configured to electrically connect different numbers of touch sensors TSto the sensing signal detection unit 104 in the case of contact touchdriving and in the case of non-contact touch driving, etc.

The selection circuit 102, in the case of contact touch deriving, mayelectrically connect the multiple touch sensors TS to the sensing signaldetection unit 104 successively.

The selection circuit 102, in the case of non-contact touch deriving,may electrically connect two or more of the multiple touch sensors TS tothe sensing signal detection unit 104 simultaneously.

The sensing signal detection unit 104 may include one or more detectionunits.

The selection circuit 102 may include one or more multiplexers whichcorrespond to and are connected to one or more detection units.

Each of the one or more multiplexers may include multiple switch groups.

Each of the multiple switch groups may include multiple switcheselectrically connected to multiple touch sensors TS.

The multiple switches may connect multiple output lines, which areconnected to the sensing signal detection unit 104, with multiplesensing lines connected to multiple touch sensors TS.

Each of the multiple switches may, in response to a selection signal,selectively connect a corresponding output line and a correspondingsensing line.

The sensing signal detection unit 104 may, as all switches included inone or at least two multiplexers are successively turned on one afteranother in the case of a contact touch (touch recognized as a fingermode), supply a driving signal to a touch sensor TS that is connected ata specific timing.

The sensing signal detection unit 104 may, as every two or more of allswitches included in one or at least two multiplexers are turned ontogether in the case of a non-contact touch (for example, touchrecognized as a hover mode), supply a driving signal to all of two ormore touch sensors TS that are connected together at a specific timing.

The selection circuit 102 may, in the case of contact touch driving,connect one touch sensor TS to the sensing signal detection unit 104 ata point of time and, in the case of non-contact touch driving, connecttwo or more touch sensors TS together to the sensing signal detectionunit 104 at a point of time.

The selection circuit 102 may, in the case of non-contact touch driving,adaptively vary the number of touch sensors TS, which are connectedtogether to the sensing signal detection unit 104, according tooccurrence of an event. In this regard, the event may occur according toa user setup input or may occur by means of a control signal thatautomatically increases or decreases the number of touch sensors inorder to improve the sensing accuracy and touch driving efficiency as aresult of non-contact touch driving.

The touch sensing circuit 100 according to the present invention mayinclude a sensing signal detection unit 104, which successively outputsdriving signals to be applied to multiple touch sensors TS, and whichdetects a sensing signal through the multiple touch sensors TS, aselection circuit 102 configured to electrically connect differentnumbers of touch sensors TS to the sensing signal detection unit 104 inthe case of contact touch driving and in the case of non-contact touchdriving, etc.

The sensing signal detection unit 104 may, in the case of contact touchdriving, output a driving signal, which is to be applied to one touchsensor TS, at a specific timing.

The sensing signal detection unit 104 may, in the case of non-contacttouch driving, output a driving signal, which is to be applied to two ormore touch sensors TS, at a specific timing.

The selection circuit 102, in the case of contact touch deriving, mayelectrically connect multiple touch sensors TS to the sensing signaldetection unit 104 successively, one after another.

The selection circuit 102, in the case of non-contact touch deriving,may electrically connect every two or more of the multiple touch sensorsTS to the sensing signal detection unit 104 successively.

The selection circuit 102 may be implemented as at least one multiplexerfor electrically connecting different numbers of touch sensors TS to thesensing signal detection unit 104 in the case of contact touch drivingand in the case of non-contact touch driving.

The selection circuit 102 may include multiple switches which switch theconnection between the multiple touch sensors TS and the sensing signaldetection unit 104 in response to a selection signal.

In the case of contact touch driving, the multiple switches aresuccessively turned on one after another, and the sensing signaldetection unit 104 may output a driving signal to a touch sensor TS,which is electrically connected through a switch that has been turnedon, at a specific timing.

In the case of non-contact touch driving, every two or more of themultiple switches are successively turned on one after another, and thesensing signal detection unit 104 may output a driving signal to two ormore touch sensors TS, which are electrically connected through two ormore switches that have been turned on, at a specific timing.

The touch sensing circuit 100 according to the present invention iselectrically connected to the multiple touch sensors TS arranged on thedisplay panel 10, and successively supplies a driving signal to themultiple touch sensors TS in a touch driving mode; in the case ofcontact touch driving, the touch sensing circuit 100 may supply adriving signal to one touch sensor TS at a specific timing and, in thecase of non-contact touch driving, may supply a driving signal to two ormore touch sensors TS at a specific timing.

The touch sensing circuit 100 according to the present invention iselectrically connected to the multiple touch sensors TS arranged on thedisplay panel 10 through multiple sensing lines and supplies a drivingsignal to the multiple touch sensors TS successively in a touch drivingmode; specifically, the touch sensing circuit 100 may supply a drivingsignal to two or more touch sensors together at a specific timing.

The two or more touch sensors TS may be touch sensors arranged on thedisplay panel 10 in adjacent positions.

The two or more touch sensors TS may be adjacent to each other in thesensing line direction or may be adjacent in a direction different fromthe sensing line direction.

For example, the two or more touch sensors TS may be touch sensorsarranged in adjacent positions in a direction parallel with the sensingline; may be touch sensors arranged in adjacent positions in a directionperpendicular to the sensing line; or may include at least one touchsensor, which is arranged in an adjacent position in the directionparallel with the sensing line, and at least one touch sensor, which isarranged in an adjacent position in the direction perpendicular to thesensing line direction.

In this regard, the sensing line that connects a touch sensor TS and thetouch sensing circuit 100 may be, for example, parallel with the dataline or parallel with the gate line.

The touch sensing circuit 100 according to the present invention iselectrically connected to multiple touch sensors TS arranged on thedisplay panel 10 and, during touch driving, supplies a driving signal tothe multiple touch sensors TS successively and detects whether a touchhas occurred or not; specifically, in the case of contact touch driving,the touch sensing circuit 100 may detect whether a touch has occurred ornot with regard to each sensing area, which corresponds to one touchsensor TS, and, in the case of non-contact touch driving, may detectwhether a touch has occurred or not with regard to each block, whichcorresponds to two or more touch sensors TS.

The touch sensing circuit 100 according to the present invention,described above, may be implemented as a touch integrated circuit.

In some cases, the touch sensing circuit 100 according to the presentinvention may be an internal circuit of a data driving circuit 24implemented as a data driving integrated circuit chip.

On the other hand, in the case of contact touch driving, a drivingsignal is applied to one touch sensor TS at a specific point of time,but, in the case of non-contact touch driving, a driving signal isapplied to two or more touch sensors TS; therefore, a larger load mayoccur during the non-contact touch driving, compared with the contacttouch driving, and a driving signal of a non-sharp type may be appliedto the touch sensors.

Therefore, use of the same driving signal during contact touch drivingand during non-contact touch driving may degrade the touch sensingaccuracy during the non-contact touch driving.

Therefore, the present invention may provide a method for usingdifferent driving signals, instead of using the same driving signal,during non-contact touch driving compared to the driving signals usedduring contact touch driving.

For example, in the case of non-contact touch driving, a driving signalVh output from the touch sensing circuit 100 and supplied to multipletouch sensors TS may have an overdriving period OP.

The degree of overdriving Vover of the driving signal Vh in theoverdriving period OP may vary depending on the position of the touchsensor TS to which the driving signal Vh is supplied.

For example, the degree of overdriving Vover of a driving signal Vh mayincrease in proportion to the distance between the device (a touchsensing circuit 100 or a data driving circuit 24 including the same)that supplies the driving signal Vh and the touch sensor TS to which thedriving signal Vh is supplied. This is because the farther a touchsensor TS is from the device (a touch sensing circuit 100 or a datadriving circuit 24 including the same) that supplies a driving signalVh, the larger the load (corresponds to the RC value) becomes, and adriving signal Vh of a higher degree of overdriving needs to besupplied.

A driving signal Vh output from the touch sensing circuit 100 andsupplied to multiple touch sensors TS in the case of non-contact touchdriving may have a larger signal intensity than that of a driving signalVf output from the touch sensing circuit 100 and supplied to multipletouch sensors TS in the case of contact touch driving (finger modedriving).

FIG. 13 is a diagram illustrating a display device driving modeaccording to the present invention, and FIG. 14 and FIG. 15 are diagramsillustrating one pulse of a driving signal used in the display devicedriving mode according to the present invention.

Referring to FIG. 13, a display device according to the presentinvention may operate in a display driving mode or in a touch drivingmode.

Referring to FIG. 13, the touch driving mode may be divided into acontact touch driving mode and a non-contact touch driving mode. As usedherein, the non-contact touch driving mode refers to a touch drivingmode having such a concept that it includes all of a hover mode, aproximity touch driving mode, etc.

Referring to FIG. 14 and FIG. 15, a driving signal Vh supplied to two ormore touch sensors TS at one timing in the non-contact touch drivingmode uses a driving signal Vf, which is supplied to multiple touchsensors TS in a contact touch driving mode, as a reference waveform andmay be, compared with the reference waveform Vf, a signal Vh that isoverdriven as much as the overdriving voltage Vover during apredetermined overdriving period OP.

For example, as illustrated in FIG. 14, the overdriving period OP inconnection with one pulse of a driving signal Vh in the non-contacttouch driving mode may correspond to the entire width HP of one pulse.

As another example, as illustrated in FIG. 15, the overdriving period OPin connection with one pulse of a driving signal Vh in the non-contacttouch driving mode may correspond to a part of the entire width HP ofone pulse.

FIG. 16A to FIG. 16D illustrate four more specific examples of drivingsignals Vf and Vh in each of a contact touch driving mode (finger mode)and a non-contact touch driving mode according to the present invention.

As in the case of an example illustrated in FIG. 16A, a driving signalgenerated and output from the touch sensing circuit 100 and may varydepending on the touch driving mode (contact touch driving mode,non-contact touch driving mode).

Referring to FIG. 16A, the driving signal Vf supplied to multiple touchsensors TS in the case of contact touch driving is a modulation pulsehaving a repeated low level period LP, which has a reference voltage Vo,and a repeated high level period HP, which has a driving voltage Vdhigher than the reference voltage Vo.

Referring to FIG. 16A, the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving is a modulationpulse having a repeated low level period LP, which has a referencevoltage Vo, and a repeated high level period HP, which has a voltageVd+Vover, Vd higher than the reference voltage Vo.

Referring to FIG. 16A, in connection with the driving signal Vh suppliedto multiple touch sensors TS in the case of non-contact touch driving,the high level period HP may include an overdriving period OP and anormal high level period NHP.

In connection with the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving, the overdrivingperiod OP within the high level period HP has an overdriving drivingperiod Vd+Vover, which is higher than the driving voltage Vd by theoverdriving voltage Vover.

In connection with the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving, the normal highlevel period NHP within the high level period HP has a driving voltageVd higher than the reference voltage Vo.

As in the case of another example illustrated in FIG. 16B, a drivingsignal generated and output from the touch sensing circuit 100 may varydepending on the touch driving mode (contact touch driving mode,non-contact touch driving mode).

Referring to FIG. 16B, the driving signal Vf supplied to multiple touchsensors TS in the case of contact touch driving is a modulation pulsehaving a repeated low level period LP, which has a reference voltage Vo,and a repeated high level period HP, which has a driving voltage Vdhigher than the reference voltage Vo.

Referring to FIG. 16B, the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving is a modulationpulse having a repeated low level period LP, which has a referencevoltage Vo, and a repeated high level period HP, which has a voltageVd+Vover, Vd higher than the reference voltage Vo.

During a first driving period Tover of a touch driving period(non-contact touch driving period) within a frame period, the high levelperiod HP may include an overdriving period OP and a normal high levelperiod NHP.

During a second driving period Tnormal of a touch driving period(non-contact touch driving period) within a frame period, the high levelperiod HP may solely include a normal high level period NHP.

Referring to FIG. 16B, in connection with the driving signal Vh suppliedto multiple touch sensors TS during a non-contact touch driving periodwithin a frame period, the normal high level period NHP may have adriving voltage Vd which is higher than the reference voltage Vo by apredetermined voltage (voltage necessary for touch sensing).

In connection with the driving signal Vh supplied to multiple touchsensors TS during a first driving period Tover of a touch driving period(non-contact touch driving period) within a frame period, theoverdriving period OP may have an overdriving driving voltage Vd+Voverwhich is higher than the driving voltage Vd by the overdriving voltageVover.

As in the case of still another example illustrated in FIG. 16C, adriving signal generated and output from the touch sensing circuit 100may vary depending on the touch driving mode (contact touch drivingmode, non-contact touch driving mode).

Referring to FIG. 16C, the driving signal Vf supplied to multiple touchsensors TS in the case of contact touch driving may be a modulationpulse having a repeated low level period LP and a repeated high levelperiod HP.

In connection with the driving signal Vf supplied to multiple touchsensors TS in the case of contact touch driving, the high level periodHP may be a normal high level period NHP, which has a high level drivingvoltage Vpd higher than the reference voltage Vo, and the low levelperiod LP may be a normal low level period NLP, which has a low leveldriving voltage Vnd lower than the reference voltage Vo.

Referring to FIG. 16C, the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving may be a modulationpulse having a repeated low level period LP and a repeated high levelperiod HP.

Referring to FIG. 16C, in connection with the driving signal Vh suppliedto multiple touch sensors TS in the case of non-contact touch driving,the high level period HP may include a high level overdriving period HOPand a normal high level period NHP.

In this regard, in connection with the high level period HP of thedriving signal Vh supplied to multiple touch sensors TS in the case ofnon-contact touch driving, the high level overdriving period HOP has ahigh level overdriving driving voltage Vpd+Vover, which is higher thanthe high level driving voltage Vpd by the overdriving voltage Vover.

In addition, in connection with the high level period HP of the drivingsignal Vh supplied to multiple touch sensors TS in the case ofnon-contact touch driving, the normal high level period NHP may have ahigh level driving voltage Vpd, which is higher than the referencevoltage Vo by a voltage necessary for touch sensing.

In connection with the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving, the low levelperiod LP may include a low level overdriving period LOP and a normallow level period NLP.

In this regard, in connection with the low level period LP of thedriving signal Vh supplied to multiple touch sensors TS in the case ofnon-contact touch driving, the low level overdriving period LOP has alow level overdriving driving voltage Vnd-Vover, which is lower than thelow level driving voltage Vnd by the overdriving voltage Vover.

In addition, in connection with the low level period LP of the drivingsignal Vh supplied to multiple touch sensors TS in the case ofnon-contact touch driving, the normal low level period NLP may have alow level driving voltage Vnd, which is lower than the reference voltageVo.

As in the case of still another example illustrated in FIG. 16D, adriving signal generated and output from the touch sensing circuit 100may vary depending on the touch driving mode (contact touch drivingmode, non-contact touch driving mode).

Referring to FIG. 16D, the driving signal Vf supplied to multiple touchsensors TS in the case of contact touch driving may be a modulationpulse having a repeated low level period LP and a repeated high levelperiod HP.

In connection with the driving signal Vf supplied to multiple touchsensors TS in the case of contact touch driving, the high level periodHP may be a normal high level period NHP, which has a high level drivingvoltage Vpd higher than the reference voltage Vo, and the low levelperiod LP may be a normal low level period NLP, which has a low leveldriving voltage Vnd lower than the reference voltage Vo.

Referring to FIG. 16D, the driving signal Vh supplied to multiple touchsensors TS in the case of non-contact touch driving may be a modulationpulse having a repeated low level period LP and a repeated high levelperiod HP.

Referring to FIG. 16D, during a first driving period Tover of anon-contact touch driving period, the high level period HP may include ahigh level overdriving period HOP and a normal high level period NHP,and the low level period LP may include a low level overdriving periodLOP and a normal low level period NLP.

Referring to FIG. 16D, during a second driving period Tnormal of thenon-contact touch driving period, the high level period HP may solelyinclude a normal high level period NHP, and the low level period LP maysolely include a normal low level period NLP.

The high level overdriving period HOP may have a high level overdrivingdriving voltage Vpd+Vover, which is higher than the high level drivingvoltage Vpd by the overdriving voltage Vover, and the normal high levelperiod NHP may have a high level driving voltage Vpd, which is higherthan the reference voltage Vo.

The low level overdriving period LOP may have a low level overdrivingdriving voltage Vnd-Vover, which is lower than the low level drivingvoltage Vnd by the overdriving voltage Vover, and the normal low levelperiod NLP may have a low level driving voltage Vnd, which is lower thanthe reference voltage Vo.

As described above, the multiple touch sensors TS may be supplied with adisplay driving voltage (for example, a common voltage that correspondsto a pixel voltage and forms an electric field) during a display drivingperiod, may be supplied with a contact touch driving signal Vf during acontact touch driving period, and may be supplied with a non-contacttouch driving signal Vh during a non-contact touch driving period.

FIG. 17 is a driving timing diagram when a frame period proceeds in atime division scheme, i.e. as a display driving period D, a contacttouch driving period TF, and a non-contact touch driving period TH,during driving of a display device according to the present invention.

Referring to FIG. 17, one frame (1 Frame) period may be time-dividedinto a display driving period D, a contact touch driving period TF, anda non-contact touch driving period TH.

Each of the display driving period D, the contact touch driving periodTF, and the non-contact touch driving period TH, into which one frame (1Frame) has been time-divided, may have the same length (Ld=Lf=Lh), or atleast one period may have a different time length (at least one of Ld,Lf, and Lh having a different value).

FIG. 18 is a diagram illustrating length-variable characteristics when aframe period proceeds in a time division scheme, i.e. as a displaydriving period D, a contact touch driving period TF, and a non-contacttouch driving period TH, during driving of a display device according tothe present invention.

Referring to FIG. 18, during image display driving, the time length Lfof the contact touch driving period TF and the time length Lh of thenon-contact touch driving period TH may vary adaptively with regard toeach other.

For example, in the case of a situation having frequently occurringcontact touches, the time length Lf of the contact touch driving periodTF may be controlled to be long, while the time length Lh of thenon-contact touch driving period TH may be controlled to be short.

In the case of a situation having frequently occurring non-contacttouches, as another example, the time length Lf of the contact touchdriving period TF may be controlled to be short, while the time lengthLh of the non-contact touch driving period TH may be controlled to belong.

FIG. 19 is a driving timing diagram when a frame period is time-dividedinto a display driving period D and a touch driving period, duringdriving of a display device according to the present invention, and thetouch driving period proceeds as one of a contact touch driving periodTF and a non-contact touch driving period TH.

Referring to FIG. 19, one frame period may be time-divided into adisplay driving period D and a contact touch driving period TF, or maybe time-divided into a display driving period D and a non-contact touchdriving period TH.

When it is determined that, after a contact touch driving period TFwithin a first frame Frame #1, a contact touch exists, the second frameFrame #2, which follows the first frame Frame #1, may be time-dividedinto a display driving period D and a contact touch driving period TF.

When it is determined that no contact touch exists, the second frameFrame #2, which follows the first frame Frame #1, may be time-dividedinto a display driving period D and a non-contact driving period TH.

FIG. 20 is a diagram illustrating parasitic capacitors Cp1 and Cp2,which occur during driving of a display device according to the presentinvention, and a load-free driving (LFD) scheme, which is a drivingscheme capable of improving touch sensing accuracy by removingunnecessary parasitic capacitances Cp1 and Cp2, for the purpose ofimproving touch sensing errors resulting from the same.

The above-mentioned load-free driving (LFD) may be defined as drivingfor removing any load that degrades the touch sensing accuracy. Theload-free driving may proceed together with main touch driving, whichsuccessively applies a driving signal to multiple touch sensors TS forthe purpose of touch sensing.

In this regard, the load that degrades the touch sensing accuracy isgenerated by a parasitic capacitance which is unnecessarily formed,while a driving signal is successively applied to multiple touch sensorsTS to conduct touch driving, between other patterns (for example, datalines and gate lines) inside the display panel 10 and multiple touchsensors TS, besides the capacitance between the pointer and a touchsensor TS, which must be formed for touch sensing. Such a parasiticcapacitance, in the case of a scheme that conducts touch sensing on thebasis of the amount of change of capacitance, may vary the amount ofchange of capacitance, thereby degrading the sensing accuracy.

Referring to FIG. 20, while driving signals Vf and Vh are supplied to atouch sensor TS during touch driving, a parasitic capacitor Cp1 may beformed between the touch sensor TS and a data line DL, and a parasiticcapacitor Cp2 may be formed between the touch sensor TS and a gate lineGL.

Such parasitic capacitors Cp1 and Cp2 act as loads in connection withtouch driving and touch sensing, and may cause touch sensing errors.

In this regard, the present invention may provide a touch driving methodcapable of reducing loads by removing unnecessary parasitic capacitancesCP1 and CP2.

According to a load-free touch driving method according to the presentinvention, while a driving signal is supplied to multiple touch sensorsTS, a load-free driving signal LFDdl, which has the same phase asdriving signals Vf and Vh, may be supplied to at least one data line DLarranged on the display panel 10.

According to a load-free touch driving method according to the presentinvention, while a driving signal is supplied to multiple touch sensorsTS, a load-free driving signal LFDgl, which has the same phase asdriving signals Vf and Vh, may be supplied to at least one gate line GLarranged on the display panel 10.

In this regard, the load-free driving signals LFDdl and FLDgl may havesignal amplitudes and signal shapes corresponding to signal amplitudesand signal shapes of driving signals Vf and Vh, which are related to acase of non-contact touch driving and a case of contact touch driving,respectively.

Accordingly, during the touch driving periods TF and TH, the differencein electric potential between the touch sensors TS and the data lines DLand the difference in electric potential between the touch sensors TSand the gate lines GL may be reduced or eliminated, thereby reducing orremoving the parasitic capacitance Cp1 between the touch sensors TS andthe data lines DL and the parasitic capacitance Cp2 between the touchsensors TS and the gate lines GL. As a result, the sensing accuracy maybe improved.

The touch sensing circuit 100 according to the present invention may beimplemented as a separate touch integrated circuit.

In some cases, the touch sensing circuit 100 according to the presentinvention may be an internal circuit of a data driving circuit 24implemented as a data driving integrated circuit chip.

Hereinafter, a data driving circuit 24, when a touch sensing circuit 100is included inside the data driving circuit 24, will be describedbriefly with reference to FIG. 21 to FIG. 23.

Referring to FIG. 21 and FIG. 22, the data driving circuit 24 mayinclude, besides a data driving unit (not illustrated), one touchsensing circuit 100 and one multiplexer MUX.

Referring to FIG. 23, the data driving circuit 24 may include, besides adata driving unit (not illustrated), two or more touch sensing circuits100-1 and 100-2 and two or more multiplexers MUX.

Referring to FIG. 21 to FIG. 23, the data driving circuit 24 accordingto the present invention may be electrically connected to multiple datalines arranged on a display panel 10, and may be electrically connectedto multiple touch sensors TS, which are arranged on the display panel10, through multiple sensing lines SL.

The data driving circuit 24 according to the present invention mayoutput a data voltage to the multiple data lines during a displaydriving mode and may successively supply a driving signal to themultiple touch sensors TS during a touch driving mode.

The data driving circuit 24 according to the present invention maysupply a driving signal Tf to one touch sensor TS at a specific timing,in the case of contact touch driving, and may supply a driving signal Thto two or more touch sensors TS at a specific timing, in the case ofnon-contact touch driving.

The data driving circuit 24 according to the present invention maysupply, in the case of non-contact touch driving, a driving signalhaving a signal amplitude larger than in the case of contact touchdriving.

The data driving circuit 24 according to the present invention mayinclude one or more multiplexers MUX, which conduct a switchingoperation to electrically connect one or more sensing lines amongmultiple sensing lines SL with the touch sensing circuit 100, such thata driving signal can be applied to one or more touch sensors amongmultiple touch sensors TS during a touch driving mode.

The data driving circuit 24 according to the present invention mayfurther include one or more multiplexers of a different kind, whichconduct switching such that, during a display driving mode, a commonvoltage is supplied to multiple touch sensors TS and, during a touchdriving mode, a driving signal is successively supplied to multipletouch sensors TS.

The data driving circuit 24 according to the present invention maysupply, while a driving signal Vf or Vh is successively supplied tomultiple touch sensors TS, a load-free driving signal LFDdl, which hasthe same phase as the driving signal Vf or Vh, to at least one data lineDL arranged on the display panel 10.

The data driving circuit 24 according to the present invention iselectrically connected to multiple data lines DL arranged on the displaypanel 10 and is electrically connected to multiple touch sensors TS,which are arranged on the display panel 10, through multiple sensinglines; the data driving circuit 24 may output a data voltage to themultiple data lines DL during a display driving mode and maysuccessively supply a driving signal Vh to the multiple touch sensors TSduring a touch driving mode in such a manner that a driving signal Vhhaving an overdriving period OP is supplied to two or more touch sensorsTS at a specific timing.

In this regard, the two or more touch sensors TS, to which a drivingsignal Vh having an overdriving period OP is supplied, may be touchsensors arranged adjacent to each other.

The two or more touch sensors TS, to which a driving signal Vh having anoverdriving period OP is supplied, may be touch sensors arranged to beadjacent in the sensing line direction.

The two or more touch sensors TS, to which a driving signal Vh having anoverdriving period OP is supplied, may be touch sensors arranged to beadjacent in a direction different from the sensing line direction.

The data driving circuit 24 according to the present invention iselectrically connected to multiple data lines DL arranged on the displaypanel 10 and is electrically connected to multiple touch sensors TSarranged on the display panel 10; the data driving circuit 24 may outputa data voltage to the multiple data lines DL during a display drivingmode and may successively supply a driving signal to the multiple touchsensors TS during touch driving, thereby detecting whether a touch hasoccurred or not.

The data driving circuit 24 according to the present invention maydetect whether a touch has occurred or not with regard to each sensingarea, which corresponds to one touch sensor TS, as illustrated in FIG.21, in the case of contact touch driving.

The data driving circuit 24 according to the present invention maydetect whether a touch has occurred or not with regard to each sensingblock, which corresponds to two or more touch sensors TS, as illustratedin FIG. 22 and FIG. 23, in the case of non-contact touch driving.

The data driving circuit 24 according to the present invention maysupply, in the case of non-contact touch driving, a driving signalhaving a signal amplitude larger than in the case of contact touchdriving.

FIG. 24 is a diagram illustrating driving timing related to multiplemultiplexers MUX 1, MUX 2, . . . , MUX 5 in connection with a touchsensing device according to the present invention.

FIG. 24 is a diagram illustrating, in connection with a case in which atouch sensing device according to the present invention includes fivemultiplexers MUX 1, MUX 2, . . . , MUX 5, how the five multiplexers MUX1, MUX 2, . . . , MUX 5 are used during each of a display driving periodD, a contact touch driving period TF, and a non-contact touch drivingperiod TH, into which one frame period has been time-divided.

Referring to FIG. 24, during the display driving period D, the fivemultiplexers MUX 1, MUX 2, . . . , MUX 5 perform switching operationssuch that a common voltage Vcom is applied to all of the multiple touchsensors TS.

Referring to FIG. 24, during the contact touch driving period TF, thefive multiplexers MUX 1, MUX 2, . . . , MUX 5 operate successively, andthe operating multiplexers perform switching operations such that adriving signal is successively applied to multiple touch electrodes TScorresponding to them.

Referring to FIG. 24, during the non-contact touch driving period TH,one or at least two of the five multiplexers MUX 1, MUX 2, . . . , MUX 5may be driven.

FIG. 25 is a diagram illustrating operations of a multiplexer MUX i(i=1, 2, . . . , 5) in connection with a touch sensing device accordingto the present invention.

Referring to FIG. 25, each multiplexer MUX i (i=1, 2, . . . , 5) of thefive multiplexers MUX 1, MUX 2, . . . , MUX 5 performs an operationconforming to each of the display driving period D, the contact touchdriving period TF, and the non-contact touch driving period TH.

Each multiplexer MUX i (i=1, 2, . . . , 5) has five channels CH1, CH2, .. . , CH5. Specifically, each multiplexer MUX i (i=1, 2, . . . , 5) maybe electrically connected to five touch sensors TS via five sensinglines SL.

Referring to FIG. 25, during the display driving period D, eachmultiplexer MUX i (i=1, 2, . . . , 5) short-circuits five channelsCH1-CH5 and supplies all of the five touch sensors TS with a commonvoltage Vcom, which has been output from a common voltage applicationunit 2520 via a sub-multiplexer 2530, via five sensing lines SL.

Referring to FIG. 25, during the contact touch driving period TF, inconnection with the corresponding multiplexer MUX i (i=1, 2, . . . , 5)which operates according to the operating order, five channels CH1-CH5are time-divided and become driving signal paths.

Referring to FIG. 25, during the contact touch driving period TF, thecorresponding multiplexer MUX i (i=1, 2, . . . , 5), which operatesaccording to the operating order, selects one channel from the fivechannels CH1-CH5 and connects (short-circuits) the selected channel withan analog front end 2500. In this regard, the analog front end 2500 maybe included inside the touch sensing circuit 100 or the data drivingcircuit 24 or may be included outside the same.

Accordingly, the corresponding multiplexer MUX i (i=1, 2, . . . , 5),specifically the five channels CH1-CH5, supply the corresponding touchsensor TS with a driving signal, which has been output from the analogfront end 2500, via a selected channel.

In this case, the corresponding multiplexer MUX i (i=1, 2, . . . , 5)receives a load-free driving signal, which has been output from aload-free driving unit 2510, via a sub-multiplexer 2530 and supplies theinput load-free driving signal to four corresponding touch sensors TSvia the four remaining channels other than the selected channel.

Referring to FIG. 25, during the non-contact touch period TH, thecorresponding multiplexer MUX i (i=1, 2, . . . , 5) selects two or morechannels from the five channels CH1-CH5, short-circuits the selectedchannels, and connects the two or more short-circuited channels to theanalog front end 2500.

Accordingly, the corresponding multiplexer MUX i (i=1, 2, . . . , 5)supplies the two or more touch sensors TS with a driving signal, whichhas been output from the analog front end 2500, via the two or moreselected channels.

Therefore, the detailed descriptions should not be construed to belimited in all aspects, but should be considered to be an example. Thescope of the present invention should be determined by rationalinterpretation of the appended claims, and all modifications within arange equivalent to the present invention should be construed as beingincluded in the scope of the present invention.

What is claimed is:
 1. A touch integrated display device, comprising: adisplay panel including a plurality of touch electrodes, the displaypanel operated in a display period of a frame or a touch period of theframe; and a touch driver circuit to provide a common voltage to thetouch electrodes during the display period and to drive the touchelectrodes with a touch drive signal during the touch period to detect atouch sensing signal responsive to a touch from the touch electrodes,wherein: in a first touch mode, the touch driver circuit drives a firstnumber of the touch electrodes with the touch drive signal during thetouch period, and in a second touch mode, the touch driver circuitdrives a second number of the touch electrodes with the touch drivesignal during the touch period, the second number of the touchelectrodes being greater than the first number of the touch electrodes,wherein a load-free driving signal having a same phase or amplitude asthe touch drive signal is driven to one or more data lines or one ormore gate lines of the display panel, during the touch period while thetouch driver circuit drives the second number of the touch electrodeswith the touch drive signal in the second touch mode.
 2. The touchintegrated display device of claim 1, wherein the first touch mode is acontact touch mode in which the touch is a physical contact made withthe touch integrated display device, and the second touch mode is anon-contact touch mode in which the touch does not make physical contactwith the touch integrated display device but is within a predetermineddistance from the touch integrated display device.
 3. The touchintegrated display device of claim 2, wherein the touch in thenon-contact touch mode is hovering over the touch integrated displaydevice.
 4. The touch integrated display device of claim 1, wherein: inthe first touch mode, the touch drive signal has a reference waveform;and in the second touch mode, the touch drive signal mimics thereference waveform but an amplitude of the touch drive signal in thesecond touch mode is overdriven by an overdrive amplitude with respectto the reference waveform during an overdrive duration.
 5. The touchintegrated display device of claim 4, wherein: the reference waveform isa pulse waveform periodically alternating between a high level and a lowlevel, and touch drive signal in the second touch mode has pulses withtwo or more different high voltage levels during the high level and twoor more different low voltage levels during the low level.
 6. The touchintegrated display device of claim 5, wherein: at least some of thepulses of the touch drive signal in the second touch mode are notoverdriven.
 7. The touch integrated display device of claim 4, wherein:the reference waveform is a pulse waveform periodically alternatingbetween a high level and a low level, and the overdrive duration is aslong as an entire width or a part of the width of a pulse of the pulsewaveform.
 8. The touch integrated display device of claim 1, wherein thetouch period of the frame includes both a first touch period of thefirst touch mode and a second touch period of the second touch mode. 9.The touch integrated display device of claim 8, wherein the touch periodof another frame subsequent to said frame includes the first touchperiod of the first touch mode but does not include the second touchperiod of the second touch mode, responsive to determining the touch insaid frame is the physical contact touch in the first touch mode.
 10. Adriver circuit for driving a touch integrated display device, the touchintegrated display device comprising a display panel including aplurality of touch electrodes, the display panel operated in a displayperiod of a frame or a touch period of the frame, the driver circuitcomprising: circuitry to provide a common voltage to the touchelectrodes during the display period and to drive the touch electrodeswith a touch drive signal during the touch period to detect a touchsensing signal responsive to a touch from the touch electrodes, wherein:in a first touch mode, the circuitry drives a first number of the touchelectrodes with the touch drive signal during the touch period, and in asecond touch mode, the circuitry drives a second number of the touchelectrodes with the touch drive signal during the touch period, thesecond number of the touch electrodes being greater than the firstnumber of the touch electrodes, wherein a load-free driving signalhaving a same phase or amplitude as the touch drive signal is driven toone or more data lines or one or more gate lines of the display panel,during the touch period while the circuitry drives the second number ofthe touch electrodes with the touch drive signal in the second touchmode.
 11. The driver circuit of claim 10, wherein the first touch modeis a contact touch mode in which the touch is a physical contact madewith the touch integrated display device, and the second touch mode is anon-contact touch mode in which the touch does not make physical contactwith the touch integrated display device but is within a predetermineddistance from the touch integrated display device.
 12. The drivercircuit of claim 11, wherein the touch in the non-contact touch mode ishovering over the touch integrated display device.
 13. The drivercircuit of claim 10, wherein: in the first touch mode, the touch drivesignal has a reference waveform; and in the second touch mode, the touchdrive signal mimics the reference waveform but an amplitude of the touchdrive signal in the second touch mode is overdriven by an overdriveamplitude with respect to the reference waveform during an overdriveduration.
 14. The driver circuit of claim 13, wherein: the referencewaveform is a pulse waveform periodically alternating between a highlevel and a low level, and touch drive signal in the second touch modehas pulses with two or more different high voltage levels during thehigh level and two or more different low voltage levels during the lowlevel.
 15. The driver circuit of claim 14, wherein: at least some of thepulses of the touch drive signal in the second touch mode are notoverdriven.
 16. The driver circuit of claim 13, wherein: the referencewaveform is a pulse waveform periodically alternating between a highlevel and a low level, and the overdrive duration is as long as anentire width or a part of the width of a pulse of the pulse waveform.17. The driver circuit of claim 10, wherein the touch period of theframe includes both a first touch period of the first touch mode and asecond touch period of the second touch mode.
 18. The driver circuit ofclaim 17, wherein the touch period of another frame subsequent to saidframe includes only the first touch period of the first touch mode butdoes not include the second touch period of the second touch mode,responsive to determining that the touch in said frame is the physicalcontact touch in the first touch mode.
 19. A method for driving a touchintegrated display device, the touch integrated display devicecomprising a display panel including a plurality of touch electrodes,the display panel operated in a display period of a frame or a touchperiod of the frame, the method comprising: providing a common voltageto the touch electrodes during the display period; driving the touchelectrodes with a touch drive signal during the touch period to detect atouch sensing signal responsive to a touch from the touch electrodes,wherein: in a first touch mode, said driving the touch electrodes with atouch drive signal comprises driving a first number of the touchelectrodes with the touch drive signal during the touch period, and in asecond touch mode, said driving the touch electrodes with a touch drivesignal comprises driving a second number of the touch electrodes withthe touch drive signal during the touch period, the second number of thetouch electrodes being greater than the first number of the touchelectrodes, wherein a load-free driving signal having a same phase oramplitude as the touch drive signal is driven to one or more data linesor one or more gate lines of the display panel, during the touch periodwhile the second number of the touch electrodes are driven with thetouch drive signal in the second touch mode.
 20. The method of claim 19,wherein the first touch mode is a contact touch mode in which the touchis a physical contact made with the touch integrated display device, andthe second touch mode is a non-contact touch mode in which the touchdoes not make physical contact with the touch integrated display devicebut is within a predetermined distance from the touch integrated displaydevice.
 21. The method of claim 20, wherein the touch in the non-contacttouch mode is hovering over the touch integrated display device.
 22. Themethod of claim 19, wherein: in the first touch mode, the touch drivesignal has a reference waveform; and in the second touch mode, the touchdrive signal mimics the reference waveform but an amplitude of the touchdrive signal in the second touch mode is overdriven by an overdriveamplitude with respect to the reference waveform during an overdriveduration.
 23. The method of claim 22, wherein: the reference waveform isa pulse waveform periodically alternating between a high level and a lowlevel, and touch drive signal in the second touch mode has pulses withtwo or more different high voltage levels during the high level and twoor more different low voltage levels during the low level.
 24. Themethod of claim 23, wherein: at least some of the pulses of the touchdrive signal in the second touch mode are not overdriven.
 25. The methodof claim 22, wherein: the reference waveform is a pulse waveformperiodically alternating between a high level and a low level, and theoverdrive duration is as long as an entire width or a part of the widthof a pulse of the pulse waveform.
 26. The method of claim 19, whereinthe touch period of the frame includes both a first touch period of thefirst touch mode and a second touch period of the second touch mode. 27.The method of claim 26, wherein the touch period of another framesubsequent to said frame includes only the first touch period of thefirst touch mode but does not include the second touch period of thesecond touch mode, responsive to determining that the touch in saidframe is the physical contact touch in the first touch mode.